Major Finding: A total of 56% of patients who continued to take Ms after
negative pH testing had positive scores on the GerdQ, suggesting that they did have GERD despite the pH results.
A
negative pH suggests that the soil pH is above ZPC leading to net negative charge (Sanchez, 1976).
Ohimain [25] recorded pH in the range of 1.3-2.9 in the Niger Delta, whereas more dramatic pH depressions were recorded in Iron Mountain mining site, California, where pH less than zero and
negative pH were recorded [26].